Blogs

SOBRE ESTE BLOG

Welcome to the Cloud/ Virtualization Management Blog, where you can read the perspectives from Cloud and Virtualization experts. This Blog provides insights into the Cloud/Virtualization Management solution, as well as technical details about specific IBM

TWEETS RECENTES

Rapid deployments with IBM Smart Cloud Provisioning

I've been impressed by the speed of
provisioning a set of virtual machines in just a few tens of seconds
using IBM Smart Cloud Provisioning. In most cases you can get a
running virtual machine in less than one minute.

The Smart Cloud Provisioning technology
has been devised and particularly optimized for managing the
following cloud infrastructure scenarios:

Infrastructure composed of
homogenous resources

High level of standardization with
a relative small set of master images used to provision many
instances from the same image

Typical life cycle of the
provisioned resources with short average time of life of provisioned
virtual instances

Many other workloads can be deployed
and easily automated on top of Smart Cloud Provisioning. For example,
traditional stateful applications can be easily deployed for simple
HA solutions. Anyway you get the maximum performances from Smart
Cloud Provisioning when operating in the context of the above
scenarios.

To achieve such high performances Smart
Cloud Provisioning has been designed focusing the attention to an
optimized virtualization infrastructure based on OS streaming: no
need to copy large image files over the network when provisioning.

Image copying is the single biggest
bottleneck in VM provisioning today both in terms of CPU, memory, I/O
and bandwidth usage. In traditional Cloud provisioning approaches all
of this overhead is system resource that is just pure overhead
(nobody builds a Cloud to provision systems - provisioning is an
overhead that is required to have systems on which business workload
is deployed, and any overhead is in conflict with the business
workload).

The key element of such infrastructure
are the so called ephemeral instances, that are virtual machines
having no persistent state. Once they get terminated all the data
associated with them is deleted as well. They are clones of a master
image and these clones will have a primary virtual disk which is
ephemeral: when the instance goes, so does its ephemeral storage
(mechanisms exist in Smart Cloud Provisioning to provide persistence,
if needed by some scenarios).

When creating a new instance, since
master images are read-only resources and are replicated across the
storage cluster, Smart Cloud Provisioning uses the Copy-on-Write
(CoW) technology and the iSCSI protocol to stream them avoiding
expensive copying. Each iSCSI session results in a valid block device
to be created in the host OS. Of course each guest OS (corresponding
to a given instance) requires a writable block device representing
the main disk of the system. All supported hypervisors have a storage
virtualization layer which includes the Copy-on-Write technology. For
example, KVM's qcow2 files can be configured to implement CoW
by referencing a backing storage device. VMWare has something called
redo files which effectively do the same thing as well. In each case,
the hypervisor can natively use the CoW file referencing the iSCSI
block device to expose a virtual block device to the virtual machine. Depending on the hypervisor and guest
OS this device will show up as something like /dev/sda or c:\. The CoW files are stored locally on the
hypervisor's file system. When the instance is terminated, the
Smart Cloud Provisioning agent will simply discard the CoW file and
check if any other instances are using the same iSCSI device. If the
device is no longer in use, the agent will also tear down the iSCSI
device.

Thanks to the above infrastructure the
action of provisioning a new virtual machine results in a very fast
and reliable process that allows to create individual systems in tens
of seconds and of peak requests of 1000s of systems per hour.

If you're interested in trying the
Smart Cloud Provisioning product, you can download a trial version
from the following link: